Chest compression-only cardiopulmonary resuscitation, also known as CPR may be at least as effective as electrical defibrillation after cardiac arrest, researchers wrote in a report published in BMC Medicine. Current guidelines for advanced cardiac life support, which were set out in 2005, recommend immediate defibrillation for cardiac arrest which occurs out of hospital.

The authors write, however, that according to experimental and clinical study findings, there is a potential benefit if the patient is pretreated with CPR before defibrillation – outcomes may be better, especially if emergency services do not arrive straight away.

The research team carried out a meta-analysis to assess the beneficial effect of chest compression-first vs. defibrillation first on survival in patients who have a cardiac arrest outside a hospital setting.

The investigators explain that not many people who suffer cardiac arrest outside a hospital setting survive. If a person’s heart suddenly stops beating, they need help immediately to get the heart pumping again.

A team of physicians from the University of Michigan Health System, as well as experts from around the world examined two rescue strategies:

  • Chest compressions first
  • Defibrillation first

They found that both strategies are effective. However, if the emergency services take longer than five minutes to arrive, chest compressions first may be best.

Lead study author Pascal Meier, M.D., an interventional cardiologist at the University of Michigan Cardiovascular Center, said:

Current evidence does not support the notion that chest compressions first prior to defibrillation improves the outcome of patients in out-of-hospital cardiac arrest; instead it appears that both treatments are equivalent.

Those who had chest compressions first had better one-year survival rates, the authors write.

The investigators collected data from four randomized trials consisting of 1,503 patients. They compared survival rates after emergency personnel performed 90 seconds or more of chest compressions before electrical defibrillation.

Senior author Comilla Sasson, M.D., an emergency medicine physician researcher at the University of Colorado, said:

The compressions-first approach appears to be as good as the defibrillation-first approach, especially if there are delays to EMS arriving on-scene. This has major policy implications.

Our study shows that chest compressions matter so even more emphasis should be placed on doing high-quality chest compressions both by laypeople providing bystander CPR and EMS providers.

According to Sasson, about 300,000 cardiac arrest cases are assessed by EMS providers in the USA each year. A mere 8% of people who have a cardiac arrest outside a hospital setting survive. It is vital to find ways to save the lives of individuals whose hearts suddenly stop.

Lives can be saved if chest compressions are administered with cardiopulmonary resuscitation, and in some cases, prompt treatment with a defibrillator. Defibrillators literally “shock” the heart back into normal rhythm.

Meier said:

Based on our study, current guidelines emphasizing early defibrillation still are important. However, since the outcomes with the chest compression-first approach were not inferior and might be even better in the long-term, and in case of longer response times, this study may have an impact on future guidelines.

Source: University of Michigan Health System

“Chest compressions before defibrillation for out-of-hospital cardiac arrest: A meta-analysis of randomized controlled clinical trials”
Pascal Meier, Paul Baker, Daniel Jost, Ian Jacobs, Bettina Henzi, Guido Knapp and Comilla Sasson
BMC Medicine 2010, 8:52doi:10.1186/1741-7015-8-52

Written by Christian Nordqvist